Coherent anti-Stokes Raman scattering (CARS) from the pure rotational Raman lines of N2 is employed to measure the instantaneous (approximately 10 ns) rotational temperature of N2 gas at room temperature and below with good spatial resolution (0.2 x 0.2 x 3.0 cu mm). A broad bandwidth dye laser is used to obtain the entire rotational spectrum from a single laser pulse; the CARS signal is then dispersed by a spectrograph and recorded on an optical multichannel analyzer. A best fit temperature is...

Topics: NASA Technical Reports Server (NTRS), GAS TEMPERATURE, NITROGEN, RAMAN SPECTRA, TEMPERATURE...

Optical sensors aboard Earth orbiting satellites such as the next generation Visible/Infrared Imager/Radiometer Suite (VIIRS) assume that the sensors radiometric response in the Reflective Solar Bands (RSB) is described by a quadratic polynomial, in relating the aperture spectral radiance to the sensor Digital Number (DN) readout. For VIIRS Flight Unit 1, the coefficients are to be determined before launch by an attenuation method, although the linear coefficient will be further determined...

Topics: NASA Technical Reports Server (NTRS), INFRARED RADIOMETERS, MAXIMUM LIKELIHOOD ESTIMATES, SOLAR...

This paper investigates the use of a neural network to determine which force actuators, of a multi-actuator array, are best activated in order to achieve structural-acoustic control. The concept is demonstrated using a cylinder/cavity model on which the control forces, produced by piezoelectric actuators, are applied with the objective of reducing the interior noise. A two-layer neural network is employed and the back propagation solution is compared with the results calculated by a...

Topics: NASA Technical Reports Server (NTRS), ACTIVE CONTROL, ACTUATORS, NEURAL NETS, PIEZOELECTRICITY,...

This mixed-methods study examined four STEM communities (BioQUEST, Project Kaleidoscope, the POGIL Project, and SENCER) in order to better understand the roles of these communities in advancing the goals of scaling STEM education reform. The project explored three key questions: (1) How do members and leaders of communities of practice (CoPs1) perceive CoP design (membership, structure, communication, activities, and organization to support new knowledge development and action) shape the...

Topics: ERIC Archive, Mixed Methods Research, STEM Education, Communities of Practice, Attitude Measures,...

A pointing error model is used in the antenna calibration process. Data from spacecraft or radio star observations are used to determine the parameters in the model. However, the regression variables are not truly independent, displaying a condition known as multicollinearity. Ridge regression, a biased estimation technique, is used to combat the multicollinearity problem. Two data sets pertaining to Voyager 1 spacecraft tracking (days 105 and 106 of 1987) were analyzed using both linear least...

Topics: NASA Technical Reports Server (NTRS), CALIBRATING, ERRORS, PARAMETER IDENTIFICATION, POINTING...

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xxxiv, 301 p. : 23 cm

Topics: Children of prenatal alcohol abuse -- Development -- Longitudinal studies, Learning disabilities --...

Source: removedNEL

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v. : 24 cm

Topics: Least squares, Personality assessment, Psychometrics

Theodorsen's circulation function relates lift to downwash in unsteady two dimensional incompressible flow. A continued fraction representation for the circulation function is described. The continued fraction converges and has a particularly simple coefficient pattern.

Topics: NASA Technical Reports Server (NTRS), ASYMPTOTIC SERIES, LEAST SQUARES METHOD, RECURSIVE FUNCTIONS,...

South Africa participated in the Third International Mathematics and Science Study (TIMSS)in 1995 and its repeat in 1999. In 1995, none of the data on school or teacher level could be analyzed to provide the context for the students' poor achievements in mathematics and science. With the 1999 data now available at both school and teacher levels in addition to the student level data, this backdrop to the results can be provided. Path analysis, using Partial Least Square analysis, was conducted...

Topics: ERIC Archive, English, Foreign Countries, International Studies, Language Proficiency, Least...

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v. : 24 cm

Topics: Least squares, Personality assessment, Psychometrics

Repeatable accuracy of hydrographic positioning was examined in terms of the two-dimensional normal distribution function which results in an elliptical error figure. The error ellipse was discussed, and two methods for conversion of elliptical errors to circular errors were given. These methods are \"circle of equivalent probability\" and \"root mean square error\" (d ) . Using the d error concept, repeatable accuracy of ranging, azimuthal, and hyperbolic systems was...

Topics: Oceanography, repeatability, predictability, circular error approximations, root mean square error,...

Results concerning interstellar extinction in the ultraviolet are reported. These results were initially obtained by using data from main-sequence stars and were extended to include supergiants and emission stars. The principal finding of the analysis of ultraviolet extinction is not only that it is wavelength dependent, but that if changes with galactic longitude in the U3 passband (lambda sub eff = 1621 A); it does not change significantly in the U2 passband (lambda sub eff = 2308 A). Where...

Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR EXTINCTION, ULTRAVIOLET RADIATION, CELESCOPES,...

Trust is one crucial prerequisite for the welfare state. However, very few empirical studies exist that help us understand the mechanisms through which trust affects the welfare state. Influencing public support for developing friendly public policies might be one of these mechanisms. In this study, we use unique micro data from 34 countries to investigate the relationship between trust and support for public education expenditures. We use the Life in Transition Survey (LiTS) conducted by the...

Topics: ERIC Archive, Foreign Countries, Trust (Psychology), Public Policy, Surveys, Expenditures, Public...

This package is designed to solve some of the elementary problems of spline interpretation and least squares fit. The subroutines fall into three basic categories. The first category involves computations with a given spline and/or knot sequence; the second category involves routines which calculate the coefficients of splines which perform a certain task (such as interpolation or least squares fit); and the last category is a banded equation solver for specific linear equations.

Topics: NASA Technical Reports Server (NTRS), INPUT/OUTPUT ROUTINES, LEAST SQUARES METHOD, SPLINE...

A linear mixing model typically applied to high resolution data such as Airborne Visible/Infrared Imaging Spectrometer, Thematic Mapper, and Multispectral Scanner System is applied to the NOAA Advanced Very High Resolution Radiometer coarse resolution satellite data. The reflective portion extracted from the middle IR channel 3 (3.55 - 3.93 microns) is used with channels 1 (0.58 - 0.68 microns) and 2 (0.725 - 1.1 microns) to run the Constrained Least Squares model to generate fraction images...

Topics: NASA Technical Reports Server (NTRS), ADVANCED VERY HIGH RESOLUTION RADIOMETER, LANDSAT SATELLITES,...

Optical implementation of the Fukunaga-Koontz transform (FKT) and the Least-Squares Linear Mapping Technique (LSLMT) is described. The FKT is a linear transformation which performs image feature extraction for a two-class image classification problem. The LSLMT performs a transform from large dimensional feature space to small dimensional decision space for separating multiple image classes by maximizing the interclass differences while minimizing the intraclass variations. The FKT and the...

Topics: NASA Technical Reports Server (NTRS), CENTRAL PROCESSING UNITS, DIGITAL FILTERS, IMAGE CORRELATORS,...

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May 18, 2008
05/08

by
Nipher, Francis Eugene, 1847- [from old catalog]

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Book digitized by Google from the library of Harvard University and uploaded to the Internet Archive by user tpb.

Topics: Magnetic measurements, Least squares

Source: http://books.google.com/books?id=-84LAAAAYAAJ&oe=UTF-8

A newly developed technique for enhanced data reduction provides an improved procedure that allows least squares minimization to become possible between data sets with an unequal number of data points. This technique was applied in the Crew and Equipment Translation Aid (CETA) experiment on the STS-37 Shuttle flight in April 1991 to obtain the velocity profile from the acceleration data. The new technique uses a least-squares method to estimate the initial conditions and calibration constants....

Topics: NASA Technical Reports Server (NTRS), ACCELERATION (PHYSICS), AEROSPACE ENVIRONMENTS, CALIBRATING,...

Subsystems aboard the Geostationary Operational Environmental Satellites 4 and 5 showed instances of anomalous changes in state corresponding to false commands. Evidence linking the anomalous changes to geomagnetic activity, and presumably static discharges generated by spacecraft differential charging induced by substorm particle injection events is presented. The anomalies are shown to be correlated with individual substorms as monitored by stations of the North American Magnetometer Chain....

Topics: NASA Technical Reports Server (NTRS), GOES 4, GOES 5, MAGNETIC ANOMALIES, MAGNETIC STORMS,...

The use is described of a sequential least squares filter in the orbit determination for the Mariner Venus-Mercury (Mariner 10) spacecraft. The orbit determination strategy outlining the use of both the sequential filter and a conventional batch filter is given. Highlighted are the mission events from launch to the first Mercury encounter with emphasis on the sequential filter performance. Advantages to the mission derived from the sequential filter are pointed out.

Topics: NASA Technical Reports Server (NTRS), MARINER VENUS-MERCURY 1973, MARINER 10 SPACE PROBE,...

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Oct 4, 2015
10/15

by
Wayman, James L.

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Technical report for period October 1982-October 1983.--cover.

Topic: TORPEDOES.,SEQUENCY THEORY--DATA PROCESSING.,LEAST SQUARES--DATA PROCESSING.,POLYNOMIALS.

Conference presentation sharing aspects of a computational biology approach to modelling and identification of human physiology.

Topics: NASA Technical Reports Server (NTRS), PHYSIOLOGY, MATHEMATICAL MODELS, BIOENGINEERING, AEROSPACE...

Geodesy is the science of measuring the gravitational field of and positions on the Earth. Estimation of the gravitational field via gravitation gradiometry, the measurement of variations in the direction and magnitude of gravitation with respect to position, is this dissertation's focus. Gravity Probe B (GP-B) is a Stanford satellite experiment in gravitational physics. GP-B will measure the precession the rotating Earth causes on the space time around it by observing the precessions of four...

Topics: NASA Technical Reports Server (NTRS), COVARIANCE, EARTH GRAVITATION, GEODESY, GEOPOTENTIAL, GLOBAL...

A system for the evaluation of interference patterns was evaluated. A picture analysis system based on a computer with a television digitizer was used for digitizing and processing interferograms.

Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, DIGITAL SYSTEMS, HOLOGRAPHY, IMAGE...

The design of closed-loop adaptive control systems based on nonparametric identification was addressed. Implementation is by self-adjusting Least Mean Square (LMS) transversal filters. The design concept is Model Reference Adaptive Control (MRAC). Major issues are to preserve the linearity of the error equations of each LMS filter, and to prevent estimation bias that is due to process or measurement noise, thus providing necessary conditions for the convergence and stability of the control...

Topics: NASA Technical Reports Server (NTRS), ADAPTIVE CONTROL, COMPUTERIZED SIMULATION, CONTROLLERS, ERROR...

Pure autoregressive (AR) models which are linear in the short term, that is when a variable can be predicted by linear regression on a limited number of past observations, are discussed. When evenly spaced observations are available, a fixed set of AR coefficients can be calculated independent of the data. For filtering purposes, such a lag structure can be implemented recursively with an efficient algorithm. The method of computing variance recursively is also derived. A complete algorithm is...

Topics: NASA Technical Reports Server (NTRS), AUTOREGRESSIVE PROCESSES, FILTERS, LEAST SQUARES METHOD,...

The Upper Atmosphere Research Satellite (UARS) has two definitive attitude determination requirements: the definitive attitude of the Modular Attitude Control Subsystem (MACS) and the definitive attitude of the gimbaled Solar-Stellar Pointing Platform (SSPP). The onboard computer (OBC) will compute the MACS attitude using a Kalman filter and will transform this attitude solution through the SSPP gimbals to calculate the SSPP attitude. The attitude ground support system (AGSS) will compute the...

Topics: NASA Technical Reports Server (NTRS), ACCURACY, ARTIFICIAL SATELLITES, ATTITUDE CONTROL, RESEARCH,...

A shake test was performed on the Large Scale Dynamic Rig in the 40- by 80-Foot Wind Tunnel in support of the McDonnell Douglas Advanced Rotor Technology (MDART) Test Program. The shake test identifies the hub modes and the dynamic calibration matrix of the rotor balance. For hub mode identification, three configurations were tested: wind tunnel scale unlocked with dampers engaged and disengaged, and wind tunnel scale locked. Test data were analyzed with a multi-degree-of-freedom time domain...

Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC LOADS, CALIBRATING, DAMPERS, HUBS, MODAL...

There are no author-identified significant results in this report.

Topics: NASA Technical Reports Server (NTRS), AGRISTARS PROJECT, COMPUTER PROGRAMS, CROP GROWTH, CROP...

The density structure of the plasmapause region was investigated using the two satellites, ISEE-1 and DE-1 to obtain complementary radial and latitudinal profiles. Data from the plasma wave receivers were to be used to obtain total electron density, and from the ion mass spectrometers to determine thermal plasma morphology.

Topics: NASA Technical Reports Server (NTRS), ELECTRON DENSITY (CONCENTRATION), PLASMA HEATING, PLASMA...

The improvement in spin vector and probe position estimates one may reasonably expect from the processing of such data is indicated. This was done by duplicating the ensemble calculations associated with a weighed least squares with a priori estimation technique applied to range rate data that were assumed to be unbiased and uncorrelated. The weighting matrix was assumed to be the inverse of the covariance matrix of the noise on the data. Attention is focused primarily on the spin vector...

Topics: NASA Technical Reports Server (NTRS), DATA PROCESSING, OUTER PLANETS EXPLORERS, PLANETARY ROTATION,...

The pressure dependence of absolute rate constants for the reaction of OH + C2H2 yields products has been examined at five temperatures ranging from 228 to 413 K. The experimental techniques which was used is flash photolysis-resonance fluoresence. OH was produced by water photolysis and hydroxyl resonance fluorescent photons were measured by multiscaling techniques. The results indicate that the low pressure bimolecular rate constant is 4 x 10 the the minus 13th power cu cm molecule (-1) s(-1)...

Topics: NASA Technical Reports Server (NTRS), ACETYLENE, CHEMICAL REACTIONS, HYDROXYL RADICALS, PRESSURE...

A generalized least squares method for deducing both total ozone and aerosol extinction spectrum parameters from Dobson spectrophotometer measurements was developed. An error analysis applied to this system indicates that there is little advantage to additional measurements once a sufficient number of line pairs have been employed to solve for the selected detail in the attenuation model. It is shown that when there is a predominance of small particles (less than about 0.35 microns in diameter)...

Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ATMOSPHERIC ATTENUATION, ERROR ANALYSIS, LEAST...

No abstract available

Topics: NASA Technical Reports Server (NTRS), SPACECRAFT LAUNCHING, LAUNCH VEHICLES, FLIGHT TESTS,...

In this thesis we propose several algorithms for rank-one updates and downdates to these decompositions with strong stability properties and efficient implementations on high-performance computers. We seek algorithms which only require O(n2) operations per update or downdate unlike recomputing the two-sided orthogonal decomposition (TSOD) in O(n3). We also desire highly regular data movement inherited in these algorithms in order to implement these efficiently on the distributed memory MIMD...

Topics: DTIC Archive, Yoon, Peter A., PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB,...

Because Multiyear estimation of at-harvest stratum crop proportions is more efficient than single year estimation, the behavior of multiyear estimators in the presence of missing acquisitions was studied. Only the (worst) case when a segment proportion cannot be estimated for the entire year is considered. The effect of these missing segments on the variance of the at-harvest stratum crop proportion estimator is considered when missing segments are not replaced, and when missing segments are...

Topics: NASA Technical Reports Server (NTRS), AGRISTARS PROJECT, CROP INVENTORIES, DATA SAMPLING, ANALYSIS...

This project concerns the development of an image reconstruction algorithm which removes noise from a corrupted image and recovers patterns and textures. The textures this algorithm detects are edges and smooth, gray scale regions. In previous attempts of this kind, images were recovered with nice edges, but blockiness remained in the smooth regions. Our goal is to recover both types of image composition. We do this by a least squares minimization method and a regularization process. The...

Topics: DTIC Archive, Choung, George P, NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MATHEMATICS,...

The Velocity data obtained from Molecular Tagging are typically located on an irregularly spaced measurement grid. To take advantage of many standard data processing techniques, the MTV data need to be remapped onto a grid with a uniform spacing. In this work, accuracy and noise issues related to the use of a least-squares-fit to various low order polynomials for the remapping of these data onto a uniformly spaced grid and the subsequent computation of vorticity from these data are examined....

Topics: DTIC Archive, Cohn, Richard K, AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST,...

A modified matrix product is explained, and it is shown that this product defiles a group whose inverse is called the incomplete inverse. It was proven that the incomplete inverse of an augmented normal matrix includes all the quantities associated with the least squares solution. An answer is provided to the problem that occurs when the data residuals are too large and when insufficient data to justify augmenting the model are available.

Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, LEAST SQUARES METHOD, MATRICES (MATHEMATICS),...

Commander Navy Recruiting Command (CNRC) has changed the Awards and Incentives system in recent years in an effort to increase recruiter productivity and promote recruit quality goal achievement. The latest awards and incentive system updates have placed increased emphasis on recruit quality in support of Navy Recruiting Commands strategic plan Recruit Force 2020. This thesis provides a detailed overview of the current Navy awards and incentives system. The thesis also attempts to estimate the...

Topics: Commander Navy Recruiting Command, Awards and Incentives System Gold Wreath Award, Recruit Force...

A chirp transform is defined for the A-step LMS adaptive predictors for linearly chirped signals embedded in additive white Gaussian noise. By converting the chirped signals to stationary baseband signals, this transform provides a different approach in analyzing the tracking performance of the LMS adaptive predictors. This transform also provides an approach of analyzing the nonlinear effects of the LMS adaptive predictor for nonstationary input signals. It is also shown that the chirp...

Topics: DTIC Archive, SPACE AND NAVAL WARFARE SYSTEMS CENTER SAN DIEGO CA, *ADAPTIVE FILTERS, PREDICTIONS,...

This study, drawing on data from the Programme for International Student Assessment (PISA) 2009, explored the influences of metacognitive and self-regulated learning strategies for reading on mathematical literacy of adolescents in Australia and Singapore. Ordinary least squares (OLS) regression analyses revealed the positive influences of metacognitive learning strategies and control strategies for reading on mathematical literacy of adolescents in Australia and Singapore. In contrast, the two...

Topics: ERIC Archive, Achievement Tests, International Assessment, Foreign Countries, Secondary School...

A relatively simple model for the microwave brightness temperature of sea surface Sun glitter is presented. The model is an accurate closeform approximation for the fourfold Sun glitter integral. The model computations indicate that Sun glitter contamination of on orbit radiometer measurements is appreciable over a large swath area. For winds near 20 m/s, Sun glitter affects the retrieval of environmental parameters for Sun angles as large as 20 to 25 deg. The model predicted biases in...

Topics: NASA Technical Reports Server (NTRS), BRIGHTNESS TEMPERATURE, GLINT, MICROWAVES, OCEAN SURFACE,...

This research addresses the decreasing worth of the Servicemembers’ Group Life Insurance (SGLI) payout based on the year a servicemember dies. The SGLI maximum has stagnated at $400,000 for over 16 years and nearly every other servicemember entitlement or benefit has increased in this timeframe. Using four principal steps, this research first determines what the SGLI maximum should be using ordinary least squares (OLS) regression and compounding inflation rates. Second, it conducts trend...

Topics: servicemembers group life insurance, SGLI, ordinary least squares, OLS

A second experimental Round Robin on the measurement of the crack opening load in fatigue crack growth tests has been completed by the ASTM Task Group E24.04.04 on Crack Closure Measurement and Analysis. Fourteen laboratories participated in the testing of aluminum alloy compact tension specimens. Opening-load measurements were made at three crack lengths during constant Delta K, constant stress ratio tests by most of the participants. Four participants made opening-load measurements during...

Topics: NASA Technical Reports Server (NTRS), ALUMINUM ALLOYS, CORRELATION COEFFICIENTS, CRACK CLOSURE,...

Airborne L- and C-band scatterometer data, taken over both vegetation-covered and bare fields, were systematically analyzed and theoretically reproduced, using a recently developed model for calculating radar backscattering coefficients of rough soil surfaces. The results show that the model can reproduce the observed angular variations of radar backscattering coefficient quite well via a least-squares fit method. Best fits to the data provide estimates of the statistical properties of the...

Topics: NASA Technical Reports Server (NTRS), AIRBORNE EQUIPMENT, BACKSCATTERING, CANOPIES (VEGETATION),...

Relationships between community colleges and the public workforce system might have an important role in promoting students' success in the labor market and in college. In particular, the co-location of American Job Centers (AJC) on community college campuses is a particularly strong form of relationship that might benefit students. Yet little is known about the impact of co-located AJCs on students. This study examines student outcomes at six community colleges in North Carolina that had...

Topics: ERIC Archive, Community Colleges, Career Centers, Outcomes of Education, Employment, Income,...

For precise time intercomparisons between a master frequency standard and a slave time scale, we have found it useful to quantitatively compare different fitting strategies by examining the standard uncertainty in time or average frequency. It is particularly useful when designing procedures which use intermittent intercomparisons, with some parameterized fit used to interpolate or extrapolate from the calibrating intercomparisons. We use the term metafitting for the choices that are made...

Topics: DTIC Archive, NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO), *FREQUENCY STANDARDS,...

Experimental intensity information is combined with numerically obtained vibrational wave functions in a nonlinear least squares fitting procedure to obtain the ground electronic state electric-dipole-moment function of carbon monoxide valid in the range of nuclear oscillation (0.87 to 1.01 A) of about the V = 38th vibrational level. Mechanical anharmonicity intensity factors, H, are computed from this function for delta V + = 1, 2, 3, with or = to 38.

Topics: NASA Technical Reports Server (NTRS), ASTROPHYSICS, CARBON MONOXIDE, DIPOLE MOMENTS, ELECTRIC...

A computer routine is suggested for selecting the optimum parameters of a theoretical model and determining the errors in them due to errors in physical measurements and for evaluating the conformity of theory with the experiment. The paper describes the specification sequence for the input data and the format of the calculation results. Sample printouts are appended.

Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, ERROR ANALYSIS, EXPERIMENTATION,...